Postoperative Curvature Loss in Three-Level Anterior Cervical Discectomy and Fusion With Zero-Profile Device

Area of Science:

• Spine surgery
• Orthopedics
• Biomechanical analysis

Background:

• Cervical curvature loss is a common complication after 3-level anterior cervical discectomy and fusion (ACDF) using Zero-Profile devices.
• The ability of Zero-Profile devices to maintain cervical sagittal alignment in 3-level ACDF is debated.

Purpose of the Study:

• Identify predictors of postoperative curvature loss (PCL) after 3-level ACDF.
• Evaluate the impact of PCL on clinical outcomes.

Main Methods:

• Retrospective review of 113 patients undergoing 3-level ACDF for cervical degenerative disc disease.
• Analysis of demographic data, radiological parameters (cervical curvature, T1 slope, C2-7 SVA, TPE distance), and clinical outcomes (VAS, NDI, JOA scores).

Main Results:

• Average PCL was 6.82°, but final cervical curvature improved by 4.33° compared to preoperative values.
• PCL correlated with preoperative curvature, preoperative T1 slope, ∆T1 slope, and ∆TPE distance.
• PCL ≥ 6° was associated with significantly higher neck VAS and NDI scores.

Conclusions:

• While 3-level ACDF with Zero-Profile devices can cause PCL, it results in improved cervical lordosis.
• Low preoperative curvature and T1 slope are potential predictors of PCL.
• PCL may negatively impact neck pain and disability, suggesting careful device consideration in specific patient groups.